Python:“突破” for 循环内的 if 语句
我知道不能“破坏” if 语句,只能从循环中“破坏”,但是,我试图从概念上阻止 if 语句在 for 循环内第一次找到“true”后进行评估。
# Import XML Parser
import xml.etree.ElementTree as ET
# Parse XML directly from the file path
tree = ET.parse('xml file')
# Create iterable item list
items = tree.findall('item')
# Create class for historic variables
class DataPoint:
def __init__(self, low, high, freq):
self.low = low
self.high = high
self.freq = freq
# Create Master Dictionary and variable list for historic variables
masterDictionary = {}
# Loop to assign variables as dictionary keys and associate their values with them
for item in items:
thisKey = item.find('variable').text
thisList = []
masterDictionary[thisKey] = thisList
for item in items:
thisKey = item.find('variable').text
newDataPoint = DataPoint(float(item.find('low').text), float(item.find('high').text), float(item.find('freq').text))
masterDictionary[thisKey].append(newDataPoint)
diceDictionary = {}
import random
for thisKey in masterDictionary.keys():
randomValue = random.random()
diceList = []
thisList = []
diceList = masterDictionary[thisKey]
diceDictionary[thisKey] = thisList
for i in range(len(diceList)):
if randomValue <= sum(i.freq for i in diceList[0:i+1]):
print 'O', i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
#diceRoll = random.uniform(diceList[i].low, diceList[i].high)
#diceDictionary[thisKey].append(diceRoll)
else:
print 'X', i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
masterDictionary 中有两个键,每个键分别包含 27 和 29 个数据点的列表。因此,循环
for i in range(len(diceList)):
将为每个键运行 0 - 26 和 0 - 28 之间的 i。这很好,但评估 if 语句时的问题是,一旦找到它,它随后对于以下所有范围项都将为 true。这是打印输出:
X 0 randomValue 0.0775612781213 prob container 0.0294117647059
X 1 randomValue 0.0775612781213 prob container 0.0294117647059
X 2 randomValue 0.0775612781213 prob container 0.0294117647059
X 3 randomValue 0.0775612781213 prob container 0.0294117647059
O 4 randomValue 0.0775612781213 prob container 0.147058823529
O 5 randomValue 0.0775612781213 prob container 0.235294117647
O 6 randomValue 0.0775612781213 prob container 0.441176470588
O 7 randomValue 0.0775612781213 prob container 0.588235294118
O 8 randomValue 0.0775612781213 prob container 0.676470588235
O 9 randomValue 0.0775612781213 prob container 0.764705882353
O 10 randomValue 0.0775612781213 prob container 0.794117647059
O 11 randomValue 0.0775612781213 prob container 0.823529411765
O 12 randomValue 0.0775612781213 prob container 0.823529411765
O 13 randomValue 0.0775612781213 prob container 0.852941176471
O 14 randomValue 0.0775612781213 prob container 0.882352941176
O 15 randomValue 0.0775612781213 prob container 0.882352941176
O 16 randomValue 0.0775612781213 prob container 0.911764705882
O 17 randomValue 0.0775612781213 prob container 0.911764705882
O 18 randomValue 0.0775612781213 prob container 0.911764705882
O 19 randomValue 0.0775612781213 prob container 0.911764705882
O 20 randomValue 0.0775612781213 prob container 0.911764705882
O 21 randomValue 0.0775612781213 prob container 0.941176470588
O 22 randomValue 0.0775612781213 prob container 0.941176470588
O 23 randomValue 0.0775612781213 prob container 0.970588235294
O 24 randomValue 0.0775612781213 prob container 0.970588235294
O 25 randomValue 0.0775612781213 prob container 0.970588235294
O 26 randomValue 0.0775612781213 prob container 0.970588235294
O 27 randomValue 0.0775612781213 prob container 0.970588235294
O 28 randomValue 0.0775612781213 prob container 1.0
X 0 randomValue 0.803308376497 prob container 0.0294117647059
X 1 randomValue 0.803308376497 prob container 0.0294117647059
X 2 randomValue 0.803308376497 prob container 0.0294117647059
X 3 randomValue 0.803308376497 prob container 0.0294117647059
X 4 randomValue 0.803308376497 prob container 0.0294117647059
X 5 randomValue 0.803308376497 prob container 0.0294117647059
X 6 randomValue 0.803308376497 prob container 0.0882352941176
X 7 randomValue 0.803308376497 prob container 0.0882352941176
X 8 randomValue 0.803308376497 prob container 0.0882352941176
X 9 randomValue 0.803308376497 prob container 0.117647058824
X 10 randomValue 0.803308376497 prob container 0.147058823529
X 11 randomValue 0.803308376497 prob container 0.205882352941
X 12 randomValue 0.803308376497 prob container 0.264705882353
X 13 randomValue 0.803308376497 prob container 0.294117647059
X 14 randomValue 0.803308376497 prob container 0.382352941176
X 15 randomValue 0.803308376497 prob container 0.441176470588
X 16 randomValue 0.803308376497 prob container 0.470588235294
X 17 randomValue 0.803308376497 prob container 0.470588235294
X 18 randomValue 0.803308376497 prob container 0.529411764706
X 19 randomValue 0.803308376497 prob container 0.588235294118
X 20 randomValue 0.803308376497 prob container 0.647058823529
X 21 randomValue 0.803308376497 prob container 0.764705882353
O 22 randomValue 0.803308376497 prob container 0.823529411765
O 23 randomValue 0.803308376497 prob container 0.882352941176
O 24 randomValue 0.803308376497 prob container 0.970588235294
O 25 randomValue 0.803308376497 prob container 0.970588235294
O 26 randomValue 0.803308376497 prob container 1.0
任何地方有“X”的地方都意味着 if 语句为假,一旦“O”开始,其余的语句将始终为真,因为概率容器的大小不断增加(最多1.0)。
我正在寻找的是一种方法,告诉循环内的 if 语句在找到第一个 true 语句后停止,然后写入字典,然后再次继续外循环。
任何帮助表示赞赏!
更新:
diceDictionary = {}
x=0
while x < 3:
import random
for thisKey in masterDictionary.keys():
randomValue = random.random()
diceList = []
thisList = []
diceList = masterDictionary[thisKey]
diceDictionary[thisKey] = thisList
for i in range(len(diceList)):
if randomValue <= sum(i.freq for i in diceList[0:i+1]):
print 'O', thisKey, i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
diceRoll = random.uniform(diceList[i].low, diceList[i].high)
diceDictionary[thisKey].append(diceRoll)
break
else:
print 'X', thisKey, i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
x = x + 1
print diceDictionary
产生:
X inflation 0 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 1 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 2 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 3 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 4 randomValue 0.500605733928 prob container 0.147058823529
X inflation 5 randomValue 0.500605733928 prob container 0.235294117647
X inflation 6 randomValue 0.500605733928 prob container 0.441176470588
O inflation 7 randomValue 0.500605733928 prob container 0.588235294118
X stock 0 randomValue 0.392225720409 prob container 0.0294117647059
X stock 1 randomValue 0.392225720409 prob container 0.0294117647059
X stock 2 randomValue 0.392225720409 prob container 0.0294117647059
X stock 3 randomValue 0.392225720409 prob container 0.0294117647059
X stock 4 randomValue 0.392225720409 prob container 0.0294117647059
X stock 5 randomValue 0.392225720409 prob container 0.0294117647059
X stock 6 randomValue 0.392225720409 prob container 0.0882352941176
X stock 7 randomValue 0.392225720409 prob container 0.0882352941176
X stock 8 randomValue 0.392225720409 prob container 0.0882352941176
X stock 9 randomValue 0.392225720409 prob container 0.117647058824
X stock 10 randomValue 0.392225720409 prob container 0.147058823529
X stock 11 randomValue 0.392225720409 prob container 0.205882352941
X stock 12 randomValue 0.392225720409 prob container 0.264705882353
X stock 13 randomValue 0.392225720409 prob container 0.294117647059
X stock 14 randomValue 0.392225720409 prob container 0.382352941176
O stock 15 randomValue 0.392225720409 prob container 0.441176470588
X inflation 0 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 1 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 2 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 3 randomValue 0.146182475695 prob container 0.0294117647059
O inflation 4 randomValue 0.146182475695 prob container 0.147058823529
X stock 0 randomValue 0.745100497977 prob container 0.0294117647059
X stock 1 randomValue 0.745100497977 prob container 0.0294117647059
X stock 2 randomValue 0.745100497977 prob container 0.0294117647059
X stock 3 randomValue 0.745100497977 prob container 0.0294117647059
X stock 4 randomValue 0.745100497977 prob container 0.0294117647059
X stock 5 randomValue 0.745100497977 prob container 0.0294117647059
X stock 6 randomValue 0.745100497977 prob container 0.0882352941176
X stock 7 randomValue 0.745100497977 prob container 0.0882352941176
X stock 8 randomValue 0.745100497977 prob container 0.0882352941176
X stock 9 randomValue 0.745100497977 prob container 0.117647058824
X stock 10 randomValue 0.745100497977 prob container 0.147058823529
X stock 11 randomValue 0.745100497977 prob container 0.205882352941
X stock 12 randomValue 0.745100497977 prob container 0.264705882353
X stock 13 randomValue 0.745100497977 prob container 0.294117647059
X stock 14 randomValue 0.745100497977 prob container 0.382352941176
X stock 15 randomValue 0.745100497977 prob container 0.441176470588
X stock 16 randomValue 0.745100497977 prob container 0.470588235294
X stock 17 randomValue 0.745100497977 prob container 0.470588235294
X stock 18 randomValue 0.745100497977 prob container 0.529411764706
X stock 19 randomValue 0.745100497977 prob container 0.588235294118
X stock 20 randomValue 0.745100497977 prob container 0.647058823529
O stock 21 randomValue 0.745100497977 prob container 0.764705882353
X inflation 0 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 1 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 2 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 3 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 4 randomValue 0.332170052306 prob container 0.147058823529
X inflation 5 randomValue 0.332170052306 prob container 0.235294117647
O inflation 6 randomValue 0.332170052306 prob container 0.441176470588
X stock 0 randomValue 0.145551106438 prob container 0.0294117647059
X stock 1 randomValue 0.145551106438 prob container 0.0294117647059
X stock 2 randomValue 0.145551106438 prob container 0.0294117647059
X stock 3 randomValue 0.145551106438 prob container 0.0294117647059
X stock 4 randomValue 0.145551106438 prob container 0.0294117647059
X stock 5 randomValue 0.145551106438 prob container 0.0294117647059
X stock 6 randomValue 0.145551106438 prob container 0.0882352941176
X stock 7 randomValue 0.145551106438 prob container 0.0882352941176
X stock 8 randomValue 0.145551106438 prob container 0.0882352941176
X stock 9 randomValue 0.145551106438 prob container 0.117647058824
O stock 10 randomValue 0.145551106438 prob container 0.147058823529
{'inflation': [0.028073642645577577], 'stock': [-0.07388514885974767]}
I understand that one cannot "break" an if statement and only from a loop, however, I'm trying to conceptually stop an if statement from evaluating after it finds a "true" the first time when it's inside a for loop.
# Import XML Parser
import xml.etree.ElementTree as ET
# Parse XML directly from the file path
tree = ET.parse('xml file')
# Create iterable item list
items = tree.findall('item')
# Create class for historic variables
class DataPoint:
def __init__(self, low, high, freq):
self.low = low
self.high = high
self.freq = freq
# Create Master Dictionary and variable list for historic variables
masterDictionary = {}
# Loop to assign variables as dictionary keys and associate their values with them
for item in items:
thisKey = item.find('variable').text
thisList = []
masterDictionary[thisKey] = thisList
for item in items:
thisKey = item.find('variable').text
newDataPoint = DataPoint(float(item.find('low').text), float(item.find('high').text), float(item.find('freq').text))
masterDictionary[thisKey].append(newDataPoint)
diceDictionary = {}
import random
for thisKey in masterDictionary.keys():
randomValue = random.random()
diceList = []
thisList = []
diceList = masterDictionary[thisKey]
diceDictionary[thisKey] = thisList
for i in range(len(diceList)):
if randomValue <= sum(i.freq for i in diceList[0:i+1]):
print 'O', i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
#diceRoll = random.uniform(diceList[i].low, diceList[i].high)
#diceDictionary[thisKey].append(diceRoll)
else:
print 'X', i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
There are two keys in the masterDictionary and each one contains a list of 27 and 29 data points respectively. Therefore, the loop
for i in range(len(diceList)):
will run i from 0 - 26 and 0 - 28 for each key. This is great, but the problem when the if statement is evaluated is that once it is found, it will subsequently be true for all of the following range items. Here is the print output:
X 0 randomValue 0.0775612781213 prob container 0.0294117647059
X 1 randomValue 0.0775612781213 prob container 0.0294117647059
X 2 randomValue 0.0775612781213 prob container 0.0294117647059
X 3 randomValue 0.0775612781213 prob container 0.0294117647059
O 4 randomValue 0.0775612781213 prob container 0.147058823529
O 5 randomValue 0.0775612781213 prob container 0.235294117647
O 6 randomValue 0.0775612781213 prob container 0.441176470588
O 7 randomValue 0.0775612781213 prob container 0.588235294118
O 8 randomValue 0.0775612781213 prob container 0.676470588235
O 9 randomValue 0.0775612781213 prob container 0.764705882353
O 10 randomValue 0.0775612781213 prob container 0.794117647059
O 11 randomValue 0.0775612781213 prob container 0.823529411765
O 12 randomValue 0.0775612781213 prob container 0.823529411765
O 13 randomValue 0.0775612781213 prob container 0.852941176471
O 14 randomValue 0.0775612781213 prob container 0.882352941176
O 15 randomValue 0.0775612781213 prob container 0.882352941176
O 16 randomValue 0.0775612781213 prob container 0.911764705882
O 17 randomValue 0.0775612781213 prob container 0.911764705882
O 18 randomValue 0.0775612781213 prob container 0.911764705882
O 19 randomValue 0.0775612781213 prob container 0.911764705882
O 20 randomValue 0.0775612781213 prob container 0.911764705882
O 21 randomValue 0.0775612781213 prob container 0.941176470588
O 22 randomValue 0.0775612781213 prob container 0.941176470588
O 23 randomValue 0.0775612781213 prob container 0.970588235294
O 24 randomValue 0.0775612781213 prob container 0.970588235294
O 25 randomValue 0.0775612781213 prob container 0.970588235294
O 26 randomValue 0.0775612781213 prob container 0.970588235294
O 27 randomValue 0.0775612781213 prob container 0.970588235294
O 28 randomValue 0.0775612781213 prob container 1.0
X 0 randomValue 0.803308376497 prob container 0.0294117647059
X 1 randomValue 0.803308376497 prob container 0.0294117647059
X 2 randomValue 0.803308376497 prob container 0.0294117647059
X 3 randomValue 0.803308376497 prob container 0.0294117647059
X 4 randomValue 0.803308376497 prob container 0.0294117647059
X 5 randomValue 0.803308376497 prob container 0.0294117647059
X 6 randomValue 0.803308376497 prob container 0.0882352941176
X 7 randomValue 0.803308376497 prob container 0.0882352941176
X 8 randomValue 0.803308376497 prob container 0.0882352941176
X 9 randomValue 0.803308376497 prob container 0.117647058824
X 10 randomValue 0.803308376497 prob container 0.147058823529
X 11 randomValue 0.803308376497 prob container 0.205882352941
X 12 randomValue 0.803308376497 prob container 0.264705882353
X 13 randomValue 0.803308376497 prob container 0.294117647059
X 14 randomValue 0.803308376497 prob container 0.382352941176
X 15 randomValue 0.803308376497 prob container 0.441176470588
X 16 randomValue 0.803308376497 prob container 0.470588235294
X 17 randomValue 0.803308376497 prob container 0.470588235294
X 18 randomValue 0.803308376497 prob container 0.529411764706
X 19 randomValue 0.803308376497 prob container 0.588235294118
X 20 randomValue 0.803308376497 prob container 0.647058823529
X 21 randomValue 0.803308376497 prob container 0.764705882353
O 22 randomValue 0.803308376497 prob container 0.823529411765
O 23 randomValue 0.803308376497 prob container 0.882352941176
O 24 randomValue 0.803308376497 prob container 0.970588235294
O 25 randomValue 0.803308376497 prob container 0.970588235294
O 26 randomValue 0.803308376497 prob container 1.0
Anywhere there is an 'X' means that the if statement was false, and once an 'O' starts, the rest of the statements will always be true because of the increasing size of the prob container (up to 1.0).
What I am looking for is a way to tell my if statement inside the loop to stop once it finds the first true statement, then write to dictionary, and then continue the outer loop again.
Any help appreciated!
UPDATE:
diceDictionary = {}
x=0
while x < 3:
import random
for thisKey in masterDictionary.keys():
randomValue = random.random()
diceList = []
thisList = []
diceList = masterDictionary[thisKey]
diceDictionary[thisKey] = thisList
for i in range(len(diceList)):
if randomValue <= sum(i.freq for i in diceList[0:i+1]):
print 'O', thisKey, i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
diceRoll = random.uniform(diceList[i].low, diceList[i].high)
diceDictionary[thisKey].append(diceRoll)
break
else:
print 'X', thisKey, i, 'randomValue', randomValue, 'prob container', sum(i.freq for i in diceList[0:i+1])
x = x + 1
print diceDictionary
produces:
X inflation 0 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 1 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 2 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 3 randomValue 0.500605733928 prob container 0.0294117647059
X inflation 4 randomValue 0.500605733928 prob container 0.147058823529
X inflation 5 randomValue 0.500605733928 prob container 0.235294117647
X inflation 6 randomValue 0.500605733928 prob container 0.441176470588
O inflation 7 randomValue 0.500605733928 prob container 0.588235294118
X stock 0 randomValue 0.392225720409 prob container 0.0294117647059
X stock 1 randomValue 0.392225720409 prob container 0.0294117647059
X stock 2 randomValue 0.392225720409 prob container 0.0294117647059
X stock 3 randomValue 0.392225720409 prob container 0.0294117647059
X stock 4 randomValue 0.392225720409 prob container 0.0294117647059
X stock 5 randomValue 0.392225720409 prob container 0.0294117647059
X stock 6 randomValue 0.392225720409 prob container 0.0882352941176
X stock 7 randomValue 0.392225720409 prob container 0.0882352941176
X stock 8 randomValue 0.392225720409 prob container 0.0882352941176
X stock 9 randomValue 0.392225720409 prob container 0.117647058824
X stock 10 randomValue 0.392225720409 prob container 0.147058823529
X stock 11 randomValue 0.392225720409 prob container 0.205882352941
X stock 12 randomValue 0.392225720409 prob container 0.264705882353
X stock 13 randomValue 0.392225720409 prob container 0.294117647059
X stock 14 randomValue 0.392225720409 prob container 0.382352941176
O stock 15 randomValue 0.392225720409 prob container 0.441176470588
X inflation 0 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 1 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 2 randomValue 0.146182475695 prob container 0.0294117647059
X inflation 3 randomValue 0.146182475695 prob container 0.0294117647059
O inflation 4 randomValue 0.146182475695 prob container 0.147058823529
X stock 0 randomValue 0.745100497977 prob container 0.0294117647059
X stock 1 randomValue 0.745100497977 prob container 0.0294117647059
X stock 2 randomValue 0.745100497977 prob container 0.0294117647059
X stock 3 randomValue 0.745100497977 prob container 0.0294117647059
X stock 4 randomValue 0.745100497977 prob container 0.0294117647059
X stock 5 randomValue 0.745100497977 prob container 0.0294117647059
X stock 6 randomValue 0.745100497977 prob container 0.0882352941176
X stock 7 randomValue 0.745100497977 prob container 0.0882352941176
X stock 8 randomValue 0.745100497977 prob container 0.0882352941176
X stock 9 randomValue 0.745100497977 prob container 0.117647058824
X stock 10 randomValue 0.745100497977 prob container 0.147058823529
X stock 11 randomValue 0.745100497977 prob container 0.205882352941
X stock 12 randomValue 0.745100497977 prob container 0.264705882353
X stock 13 randomValue 0.745100497977 prob container 0.294117647059
X stock 14 randomValue 0.745100497977 prob container 0.382352941176
X stock 15 randomValue 0.745100497977 prob container 0.441176470588
X stock 16 randomValue 0.745100497977 prob container 0.470588235294
X stock 17 randomValue 0.745100497977 prob container 0.470588235294
X stock 18 randomValue 0.745100497977 prob container 0.529411764706
X stock 19 randomValue 0.745100497977 prob container 0.588235294118
X stock 20 randomValue 0.745100497977 prob container 0.647058823529
O stock 21 randomValue 0.745100497977 prob container 0.764705882353
X inflation 0 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 1 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 2 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 3 randomValue 0.332170052306 prob container 0.0294117647059
X inflation 4 randomValue 0.332170052306 prob container 0.147058823529
X inflation 5 randomValue 0.332170052306 prob container 0.235294117647
O inflation 6 randomValue 0.332170052306 prob container 0.441176470588
X stock 0 randomValue 0.145551106438 prob container 0.0294117647059
X stock 1 randomValue 0.145551106438 prob container 0.0294117647059
X stock 2 randomValue 0.145551106438 prob container 0.0294117647059
X stock 3 randomValue 0.145551106438 prob container 0.0294117647059
X stock 4 randomValue 0.145551106438 prob container 0.0294117647059
X stock 5 randomValue 0.145551106438 prob container 0.0294117647059
X stock 6 randomValue 0.145551106438 prob container 0.0882352941176
X stock 7 randomValue 0.145551106438 prob container 0.0882352941176
X stock 8 randomValue 0.145551106438 prob container 0.0882352941176
X stock 9 randomValue 0.145551106438 prob container 0.117647058824
O stock 10 randomValue 0.145551106438 prob container 0.147058823529
{'inflation': [0.028073642645577577], 'stock': [-0.07388514885974767]}
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Break 将终止“最近的封闭循环,如果循环有,则跳过可选的 else 子句一。”外循环将继续下一次迭代。因此,您不是“中断 if”,而是将 if 包含在循环中。在中断之前,您只需将
diceList[0:i+1]
中的所有值设置为diceList[ 0:len(diceList)+1]
为 true。Break will terminate "the nearest enclosing loop, skipping the optional else clause if the loop has one." The outer loop will just continue with the next iteration. So you are not "breaking the if" but the loop the if is enclosed in. Before the break, you can just set all values from
diceList[0:i+1]
todiceList[0:len(diceList)+1]
to true.一种方法是在内部代码中引发异常,并在 for 循环内捕获该异常并继续循环。
One method is to raise an exception in the inner code, and catch it inside the for loop and continue the loop.
那么,您知道该陈述为 True 的条件是什么?我认为这可能是“如果最后一个语句为 True”,但在您的示例输出中,您最终会回到
False
?无论哪种方式,请考虑将其作为某种第一个条件添加到您的 if 中:
如果第一部分被评估为 False (即您已经知道它是 True ),Python 不应该评估第二项
和
(因为它现在不可能是True
)并继续前进。您只需要添加另一个 else 子句(因此可能使else
成为elif
)并在那里处理它。注意:这种方式可能有点棘手,具体取决于您需要做什么才能确定您是否已经知道该语句是
True
:\So what are the conditions that you know the statement is
True
? I thought it might be "if the last statement was True", but in your sample output you eventually go back toFalse
?Either way, consider adding this as some sort of first condition to your if:
If the first part is evaluated as False (i.e. you already DO know it's
True
), Python shouldn't evaluate the second term of theand
(since it now can't beTrue
) and move along. You'd simply need to add another else clause (and so maybe make theelse
anelif
) and handle it there.NB: This way could be a bit hacky depending on what you'd need to do in order to determine whether you already know the statement is
True
:\据我了解,您正在尝试保存循环其余部分的 if 比较。我认为你必须将循环分成两个循环,一个循环执行 if 语句并找到分区点,第二个循环则简单地跳过比较。您可以将当前正在处理的 i 保留在循环外部的变量上,然后在第二个循环中从该点继续。
From what I understand you're trying to save the if comparison for the remainder of the loop. I think you have to split the loop you have into two loops, one that does the if statement and finds the partition point and then the second that simply skips the comparison. You can keep the current i you're working on on an variable external to the loop, and then continue from that point in the second loop.
如果您确定要跳出 if 语句代码块,并且只要“break”有效就可以这样做,则可以将“break”放在您想要的位置,然后将整个 if 语句块放在循环一次迭代。
If you are sure that you want to break out of the if statement block of code, and would do so if only "break" would work, you can put "break" where you wanted it and then place the entire if statement block in a loop with a single iteration.